Puzzling situation

Here is something that is confusing and bugging me. 1987 Brougham 307.

The person (idiot) that I bought this car from used stop leak to "fix" a leaking water pump. Naturally, it failed and he had to replace the water pump anyway. By the way, he clogged the heater core with this and put a bypass in. He did this himself and failed to flush the cooling system out so all this brown/rust colored crap was all over the inside the radiator, reservoir, etc. I only drove the car around 80 miles after acquiring it since I wanted to replace the radiator, reservoir, hoses, thermostat, and thermostat housing before driving this vehicle much. As I was going over to a friends house to replace everything, (about 15 minutes into the 30 minute drive), there was some white smoke coming from the rear of the car. I could not tell if it was directly coming from the tailpipe but put the car in neutral, revved it a bit, and more smoke came out...I think it may be a safe assumption that it was coming from the tailpipe.

I got the car to his house (no engine lights, coolant light, etc), parked it and open the hood. When I started on this drive, I added coolant to the reservoir and it was green...when I got there, the reservoir was nearly empty with a little bit of brown/rust colored fluid at the bottom. Naturally, I thought the head gasket was shot but figured I'd replace what I was going to, in the first place. A pressure test indicated that the radiator had a leak, as well. All in all, the radiator, cap, hoses, thermostat, and thermostat housing were replaced, along with multiple flushes and back flushes (with a garden hose) through the engine block until the water ran clear. Put everything back together and the vehicle had no smoke and no issues . After driving it for another 50 miles, I flushed the radiator and engine block out again. Refilled with coolant/water. Another 50 miles later, the coolant level is steady and no white smoke is coming out the tailpipe.

Any idea as to what caused the white smoke in the first place? I haven't heard of white smoke out the tailpipe without it being a head gasket issue. Hoping I didn't buy a lemon :fingers crossed:

Re: Puzzling situation

Thanks for the advice. I should have mentioned that, according to the guy that helped me work on the car, the old thermostat was junk. I also should've mentioned that the temperature was about 66 degrees (don't think that's cold enough to see normal exhaust). Is there anything that the white smoke could've been, other than a bad head gasket? There was not a lot of smoke...just enough to see drifting. Anything to possibly do with the stop leak and cruddy coolant/leaking radiator/thermostat? I just don't understand that if it is a head gasket, why the car is not overheating and why the smoke stopped after flushing the system and putting in a new radiator/thermostat. It's been driven hard over 2 hours with no coolant loss or smoke...

Re: Puzzling situation

White smoke is very common when it's cold out or if a car has gone thru a temperature change like being pulled out of a garage or building and being parked outside. It's the whole condensation thing. If it's burning antifreeze you'll tell from the smell.

Re: Puzzling situation

Well, smoke out the exhaust either means you're burning coolant or oil or not burning fuel correctly. If its coolant, you're leaking at the head gasket or intake gasket. Oil means you're leaking from the piston rings, valve guides or PCV system. If its fuel related, you're running rich or lean. White smoke from coolant can be hard to tell from the blue smoke of fuel problems so you could put a fuel pressure gauge on it just to rule out fuel problems. I just remembered, on my Olds 307 powered brougham, my intake gasket went on me but it didnt leak into the engine, only outside. How was it running when you were seeing the smoke?

Re: Puzzling situation

The engine appeared to run normal with the bit of white smoke out the tailpipe. No notice in loss of power or anything. I'm pretty sure that the intake manifold gasket is leaking oil, as I can see it from the outside. Maybe that could be my issue (if it's leaking internally)? I guess that still doesn't explain why the car was driven 50-60 miles with no smoke, had 15 minutes of light white smoke before replacing the radiator/thermostat/cap/hoses, and now I haven't had a single puff of smoke since....even with the throttle completely open.

The valve cover gaskets leak a bit too so it doesn't appear it would hurt to replace them as well, if I take the manifold off. Any tips or more suggestions would be great.

Re: Puzzling situation

White steam from a coolant leak dissipates quickly because its steam not smoke. White smoke on the other hand, lingers around the car. I wonder if the trans is slightly overfilled and the white "smoke" was trans fluid being expelled from the trans vent. That would account for it finally quitting. If the trans is overfilled, it will vent until the foaming of the fluid stops and the level is close to normal. Trans fluid level should alway be just below the full mark even with the trans up to operating temp. The fluid expands as it warms so if full cold, it will be overfilled warm.

Re: Puzzling situation

Carnut....thank you for that. I think that makes a lot of sense and I'll tell you why. The week previous, I dropped the transmission pan and replaced the fluid/filter. When I refilled the transmission fluid and checked the level, it read a little more than halfway on the XXXX part of the dipstick. I added more fluid but I think I probably added too much and this is what it could've been. I didn't drive the car at all, during that week so that was the first time it had a chance to burn it off (when I was driving it the 30 minutes).

After a little research, I found that a bad vacuum modulator valve (mounted on the side of the transmission) can cause very similar symptoms. The car does seem to rev quite a bit, between 1st and 2nd gear, before shifting and that shift is definitely the hardest.

Re: Puzzling situation

Dont over think this scenario! Pull the vac. hose off the modulator, if it in fact it has one, and verify no fluid drips from that hose. You appear to have a TV cable misadjusted too short which will give you late/ harsh upshifts. Do a GOOGLE search to see how this simple cable is adjusted. If left misadjusted, transmission damage can occur. I believe you have a 2004R trans in that car.

Your car doesn't have a vacuum mod on the tranny so your problems are not related to the tranny. Your tranny is controlled by an adjustable cable. Your issues are engine related. Just do a compression test to get straight to the point.

Re: Puzzling situation

On another note...yes, the car does not appear to have a vacuum modulator. Looks like a metal rod with a clip at the end that attaches to the drivers side of the transmission. I assume that is what gets adjusted? I'll be searching google for more information